Rob Tavaglione set out to test three factors: Can these shields reduce noisy DAWs effectively? Which shield produces the best vocal sound? And which one attenuates leakage the most?

The consensus is already there: Microphone isolation shields are really helpful in mitigating bad acoustic recording environments, reducing leakage and helping track sweeter vocals. I’ve also been using the Mudguard v2 around the studio for various apps when the need presents itself—taking the room out of vocals, tracking ultra-dry in-your-face acoustic instruments and sometimes making my drum kit ambience mics a little less ambient.

The Mudguard v2 uses a non-perforated plastic shell (16” x 10” x 14” WDT) lined with Auralex’s 1.25-inch Studiofoam wedge foam. It mounts to your mic stand with a steel L-bracket, which, along with the supplied fittings, will fit most mics, but not really tall ones. The mic should be positioned about 5.5 inches from the shield’s rear to ensure both a natural sound and reasonable isolation. The sides of the shell are not concave but convex, which reportedly focuses reflected sound away from the mic, not channeling sound toward the center (like most designs on the market), which can cause phase smearing and coloration.

I also use another mic shield, the Primacoustic VoxGuard, and thought that some direct comparisons could be informative, especially since the Mudguard uses basically the same materials and has the same relative size (unlike more expensive models with metal construction and venting designs, like the sE Electronics Reflexion Filter). I set out to test three factors of importance to consumers: Can these shields reduce noisy DAWs effectively? Which shield produces the best vocal sound? And which one attenuates leakage the most?

For testing, I used a Neumann TLM 103, which I chose for its cardioid pattern, ample off-axis response and side-address design, as end-address mics don’t fit ideally in either shield tested. With a reference-clean AMS-Neve 4081 mic preamp, I did a series of tests with the only difference being the shield used.

Background Noise: One can only imagine how many vocals are cut in control rooms today, so the ability to reject some hard drive clicking, transformer hum and fan noise is a big reason for these shields. I set up my mic just a few feet from my isobox (with its four built-in fans), which houses the computer, and cracked the door to allow more noise out, like in a noisy one-room project studio. Both shields removed a significant amount of the DAW noise—not all of it, but enough to be noticeable and worthwhile. The Primacoustic shield got the noise floor 3 dB quieter, but the Mudguard attenuated high frequencies a little more for darker leakage.

Acoustic Guitar: I played my Taylor acoustic in three positions relative to the shields—on-axis, 180 degrees off-axis and 90 edges off-axis. When on-axis, I got a slightly more natural sound from the Mudguard, as the VoxGuard tone had a low-mid emphasis, slightly dulled, and the Mudguard sounded like it wasn’t there, just neutral. Both rejected the guitar’s sound well at 180 degrees, with the VoxGuard attenuating a little more overall, about 3 dB more. At 90 degrees off-axis, both offered only moderate attenuation in equal amounts.

Drums: Another popular use of these mic shields is as a hi-hat isolator, as well as focusing distant mics and isolating outside kick mics. With hi-hat, I found the wider VoxGuard kept more hi-hat sound out of the room, but that the sound captured from the hat was a little clearer and crisper via the Mudguard. As far as isolating kick goes, the VoxGuard kept a little more hat, snare and floor tom out of the kick mic, but neither did much to stop the huge bass content of the floor tom from getting through, filtering out mostly highs and some mids. The VoxGuard blocked out a little more snare, but both blocked out quite a bit of hi-hat equally. Both did enough to negate the need for a “kick tunnel” of stands/blankets.

Vocals: In a nicely treated tracking room, you don’t need a mic shield to get a good vocal sound, and both models tested were able to remove any hint of such a nice room and achieve that totally stark, dry, NPR-like sound. In an untreated and way-too-lively stairwell, both did an effective job of reducing the natural reverb’s audibility and greatly improving the results to the point of usability. But the Mudgaurd sounded better, with a more natural tone, absent any muddiness (as the name suggests) and with a little more clarity.

All things considered, I’d say that the Mudguard v2 earns its $149 price for helping block out room noise, reduce leakage and achieve the most natural sounding frequency balance, especially for vocals. For that matter, the Primacoustic VoxGuard did an even better job of reducing leakage and likewise reduced room noise, too, even if it didn’t quite have the flat response or clarity of the Mudguard. It deserves mention that both could help achieve isolation when miking an electric guitar cabinet, but there are models specifically for that purpose now.